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  1. #1 Shutter question 
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    Hi I am experimenting with trying to capture a hand crank style video capturing by messing with the shutter. On my camera I can get the required look of a 1/3 shutter but it only lets me take photos at this shutter. Visually on the camera screen it looks like how I want it to capture but in video mode my shutter only opens up to 1/24 which seems to equate to a 360 shutter angle. So I guess my question is can you open up to a shutter angle wider than 360 or is that physically impossible... I’m a bit confused anyhow and wondering if someone can set me straight :)
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  2. #2  
    A shutter at 360 degrees is open 100% of the time -- you can't have a camera take a picture 24 times a second, for example, and expose each frame for longer than 1/24th of a second without breaking the laws of physics. There are or were video cameras that accumulated exposure but basically they were dropping the frame rate to do it.

    The look of hand cranked movies in the silent era was not due to longer shutter times. The look was due to shooting at 16 to 18 fps (which meant slightly longer exposure times at 180 degrees of 1/32 to 1/36 per frame instead of 1/48th at 24 fps) but with a handcrank so the speed was not consistent, nor the exposure. So these subtle surges in speed and brightness along with the lower-than-24 frame rate was part of the look, plus whatever technique or speed was used to show the footage today, whether leaving it to look sped-up or transferring it at the shooting speed and converting it to display speed. And truth is that as camera operators got better, the look from hand cranking as opposed to using a motor was fairly minor.

    The opening of the movie "Avalon" was example was shot at 16 fps on film and optically repeated every other frame to create normal speed at 24 fps projection, but the odd cadence in the resulting motion gave the impression of a silent movie.
    David Mullen, ASC
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  3. #3  
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    Thanks David. It’s getting clearer in my mind now :) more experimenting to do though. I’m playing around with the filmic pro app on my iPhone because my video cameras don’t allow a ‘time base’ to be lower than 24fps! Which is crucial to the effect I’m trying to achieve... so I’m playing around with capturing at 3fps and playing back at 3fps, not 24fps because if you play back at 24fps it just speeds up the visuals anyway very interesting but much more playing around with is needed to fullying grasp this concept.
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  4. #4  
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    To further illustrate... 3fps played back at 24fps : https://youtu.be/rlHX4nyid-Y
    And 3fps played blacked at 3fps: https://youtu.be/DPYXTrx1-68

    Very interesting you truly do learn something new everyday :)
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  5. #5  
    That's interesting but nothing like the way hand-cranked silent movies looked, usually shot 16 to 18 fps with a 180 degree shutter...

    I mean, look at Buster Keaton's "The General" -- the motion is not that different than modern 24 fps movies:
    https://www.youtube.com/watch?v=Ytd7tKEvz2M

    Go back even earlier to Georges Melies:
    https://www.youtube.com/watch?v=xLVChRVfZ74

    It certainly doesn't look like 3 fps or even 8 fps motion...
    David Mullen, ASC
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  6. #6  
    I own three and have never really messed with the feature much, but you could try getting your hands on a VariCam, as they allow you to actually ramp the frame rate up and down live as you shoot. Bumping the frame rate up and down continuously from the base rate you want may give you the effect you want, since this was what was basically happening(unintentionally) with real hand cranking.
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  7. #7  
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    i've experimented with slowing 24fps footage down in post. 25% reduction nets 18FPS. Drops one out of four frames. To get the same motion blur over a frame interval as shooting at 18fps I set the shutter angle to 240 degrees at 24fps.

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  8. #8  
    Take a look at the opening of "Avalon", shot by Allen Daviau at 16 fps and step-printed back to 24 fps:
    https://www.youtube.com/watch?v=8vWKJbQT06o
    David Mullen, ASC
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  9. #9  
    Red has speed ramp set your framerate to somthing like 18fps and asign a hotkey to ramp over some duration of time to 24 or such and then back to 18 and let the speed go back and forth. That would mimic an ill crancked super 8 or 16mm camera you can also shoot 2k to get closer to the 16mm sensor size but closing down more on 35mm sensor and push back the stop loss with iso gives the same effect plus nicer more organic grain structure. The last thing that most miss when trying to mimic old narow film format is the gate weave. The picture should be flapping in the frame in :d space not just xyz movement but preferably like a flag flapping in the wind and also preferably do the setting so it loops over a couple of frames and with a pumping flicker and focus as camera and projector mechanisms where far from perfect especially on the formats that only had perfs on one side.

    If shooting normal framerate and trying to achive it all in post then I usually speed upp somthing like 115% and then stretch out to original length without interpolation and in frame mode causing a loss of frames and double frames. Which I think works quite well. Did it on this event thing I shot for IWC.

    https://app.frame.io/presentations/7...d-5f1a5935c6f9
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  10. #10  
    Senior Member Joe Taylor's Avatar
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    I believe the Arri D-20 and D-21 had a crank (much like the crank for the 435) that allowed the operator to actual hand crank a digital cinema camera. I've looked for shot examples but have never tracked one down.
    Website: www.JoeTaylorCinema.com

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